mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Hardness: 3 on Mohs scale; Color: Orange to honey-yellow; Luster: Vitreous to waxy/pearly; Crystal structure: Trigonal/Hexagonal; Cleavage: Perfect rhombohedral; Specific gravity: 2.71.

Hardness: 3 on Mohs scale
Color: Orange to honey-yellow
Luster: Vitreous to waxy/pearly

Identified June 17, 2026More mineral →

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Physical properties

Hardness: 3 on Mohs scale; Color: Orange to honey-yellow; Luster: Vitreous to waxy/pearly; Crystal structure: Trigonal/Hexagonal; Cleavage: Perfect rhombohedral; Specific gravity: 2.71.

Formation & geological history

Formed primarily through chemical precipitation in sedimentary environments such as hot springs, caverns, or marine settings. The orange color is typically caused by iron oxide inclusions or other trace impurities trapped during formation.

Uses & applications

Used as a decorative stone, in lapidary work for carvings and spheres, as a collector's specimen, and occasionally as a source of lime in industrial processes.

Geological facts

Orange calcite is often called the 'stone of the mind' and is highly sought after by metaphysical collectors. It is chemically identical to limestone and marble but exists in a more pure crystalline form.

Field identification & locations

Identified in the field by its characteristic rhombohedral cleavage, softness (can be scratched by a copper penny), and a strong effervescent reaction when exposed to dilute hydrochloric acid. Commonly found in Mexico, USA, and Brazil.